Grinding mill



Aug. 13, J R HALL GRINDING MILL Filed March 27, 19 44- 707.02 fiHa-ZZ,

Patented Aug. 13, 1946 GRINDING MILL John R. Hall, Chicago, 111.,assignor to International Harvester Company, a corporation of New JerseyApplication March 27, 1944, Serial No. 528,224

' l v V V This invention relates to a new and improved grinding mill andhas for one of its principal objects the provision of means forautomatically releasing the cylinder concave upon entranc of some hardmaterial which "would normally tend to break parts of the grinding millunless the operation of the mill was halted in some way.

An important object of this invention is to provide a feed grinding millcapable of having its concave released from its operative positionadjacent the cylinder either manually or automatically.

Another and still further important object is to provide a hingedconcave yieldably held in position adjacent a cylinder which isautomatically releasable and capable of repositioning by a mere manualswinging of the concave.

Other and further important objects willbecome apparent from thedisclosures in the following specification and accompanying drawing, inwhich:

Figure 1 is a longitudinal sectional view of the grinding mill of thisinvention;

Figure 2 is a sectional view taken on the line 22 of Figure 1; and

Figure 3 is a sectional view similar to Figure 2 with the concave inreleased position.

As shown in the drawing, the reference numeral l indicates generally ahousing for a grinding mill and includes a feed inlet hopper I l whichpermits grain. or other material to be ground to reach a cylinder l2which, as shown in Figure 1, has a spiral flighting I3 extending aroundthe periphery and lengthwise of the cylinder. closely adjacent thecylinder I2 50 that material carried by the spiral flighting i3 iscompressed and partially ground against the concave I l. In order tomore thoroughly grind material, the inner surface of the concave I4 isroughened as at I5 and shown in all thefigures of the drawing.

The concave I4 is hinged above the horizontal center-line of thecylinder 12 at Is to lugs H which form an integral part of a casting l8bolted or otherwise attached as shown in Fi ure 2. A cutting blade 2| isbolted to the upwardly extending flanges l8 at 22 and extends inwardlyto a point very close to the periphery of the cylinder spiral flightingl3. The cylinder I 12 rotates in a counter-clockwise direction as viewedin Figure 2 and indicated by an arrow 23. It will be apparent that asmaterial to be ground is fed longitudinally by the spiral flight- Aconcave i4 is positioned beneath and 1 Claim. (01. 241---239) 2 ing {3it Will be positively sheared by the cutting bladeZl.

The lower end of the semicylindrical concave I4 is equipped with anoutwardly extending radial flange 24, the surface of which is inclinedas'shown at 25. The flange 24 is adapted to abuttingly engage a member26 which is rigidly afiixed to the hopper walls H. A release lever 21 ishinged at 28 on rearwardly extend-ing hinge lugs 29 of the member 26.The forward portion of the lever 27 has an inverted V-shaped surfaceincluding inclined sides 30 and 3| and an apex 32. i

The lever 21 has a relatively large opening 33 through which a long bolt34 is adapted loosely to pass. The bolt 34 extends through the hopperwall H, through the member 26, and thereupon through the opening 23 inthe lever 21. The bolt 34 is retained in its position by means of a head35 at its upper end and a nut 36 at its lower end. A spring 3'! isinterposed between the nut 36 and the lever 21, thereby resilientlymaintaining the lever 21 in its uppermost position as shown in Figures 2and 3. The yieldable latch is below the horizontal centerline of thecylinder and on the opposite side from the hinge Hi.

In Figure 2 the concave I4 is yieldably locked in an operative positionadjacent the cylinder l2. The inclined surface 30 of the lever 21engages the inclined surface 25 of the concave flange 24. It is possiblein feeding grain or other material to a grinding mill to accidentallyput in some foreign object such as a rock which would be hidden by thegrain and which would tend to cause great damage to the machine parts ofa feed grinder unless some safety means was provided. At the presenttime wooden shear pins are employed to a great extent to prevent suchaccidents, but this method has proved inconvenient in reassembling thegrinding mill in order to resume operation.

The action of the'present device is to automatically permit the inclinedsurfaces 24 and 30 to slide apart relative to each other and thus permitthe concave to swing about its hinge I5 and take the position shown inFigure 3. The releasing of the concave is instigated upon overcoming theforce of the spring 31. Therefore, when an obstruction enters thecylinder and concave, a downward force is applied to the concave M whichacts directly on the spring 31 through the lever 21. It is obvious thatno parts will be broken, and that the obstruction, whatever it theconcave I4 is manually swung about the hinge l6 so that its flang 24will ride up on the inclined surface 3! of the lever 21. Inasmuch as theconcave M has a fixed arcuate movement, it will be apparent that therelease lever 21 must yield downwardly against the action of the spring31. Immediately upon the flange 2 4 riding over the apex 32 of thelever2l, the spring; 3;! forces: the lever 2T upwardly so that theflange 24' rides down the incline 30 and thereupon locks the con; cavein the position shown in Figure 2.

The spiral flighting l3 of the cylinder [2. 126.1 forms twofunctionsfirst, that of preliminarily breaking up material to be; groundandl e nsir that of feeding the grain longitudinally of the cylinder I2to grinding plates 39 and 48. The

plate 31 is permanently fixedtn the; housing 10;

of the grinding mill, and the plate 49 rotates with the cylinder [2.Material to be ground is extruded between the plates 39 and 40 and thencarried by thrower blades- 41 to some depositorya The means for drivingthe cylinder l2 and plat'e 4llma-y-be one'oi several devices sucl'ra'san' electric-motor or frornthepower 'GEKBfOfi Off a tractor; whicheveris-a-vailable; A lever 52 is provided on theoutside of the-feed grinderand permits adjustment of the plates $9 and Ml with respect to eachother. a

Anopening 43 is provided inone the side walls I i) of the-feed grinderto enable an operater toinserthis arm and pull d'ewn on the lever; 21'

and hence manually release the concave M. A plate M hinged as at 45 orotherwise fastened is adapted to cover the opening 43. Such manualreleasing may be necessary in cleaning out the feed grinder Or for anyother purpose which is deemed advisable.

It will be apparent that herein is provided a novel; concave, for feedgrinders having a resilient locking means which permits automaticreleasing T of the concave as well as automatic relocking of the concaveupon giving the concave a manual swing,

The intention is to limit the invention only within the; scope of: theappended claim,

What iscl'aimedis: In a material treating machine comprising a housing;arotatable cylinder within said housing,

a concave partially surrounding said cylinder, said concave being hingedat one side of said cylinder and fastened by means of a yieldablelatchat" the other side of saidcylinder; said yieldable latch havingmeans for" automatically releasing the concave upon the attainmen-t of apredeterminedpressurebetween said cylinder and concave; and furthermeans for manuallyreleasing said ceneave, said 'la'tch comprising ahinged lever -havinganinclined porticn-slidably engaging abe'veled lugonthe-concave, aspringadapted-to normally hold-said lever in: engagementwithsaid beveled-lug. V V

